my 13 year old cocker poo seems to be retching for the past 24 hours. it's as if he's trying to get air into his lungs, but then he seems to have a vomitting like reaction. after giving him a milk bone dog biscuit this a.m. he threw up as he walking down the stairs and then proceed to throw up outside. he is eating, doesn't seem depressed, but it's very hot where i am (100 degrees today) . he's resting now, breathing normally and sleeping in the air conditioned bedroom. need to know what to do here.